Aspirator nozzle for blow guns or the like

ABSTRACT

An aspirator nozzle for a blow gun is disclosed herein. The nozzle includes an air passageway extending from the inlet end to the outlet end thereof. The nozzle also includes an aspirator bore which extends through the nozzle transversely to the air passageway and which communicates therewith. The preferred embodiment utilizes a single aspirator bore which extends completely through the nozzle transversely to the air passageway. A modified form of the nozzle utilizes a plurality of aspirator bores which extend radially outwardly and rearwardly from the air passageway. In both of the embodiments, the aspirator bore communicates with the air passageway at the location wherein the air flow has the greatest velocity as it passes through the nozzle. The nozzle may be used with a blow gun having a pressure regulated, manually operated valving. The nozzle may also be used with a blow gun having a poppet type, manually operated valve means. In the latter environment, an air restrictor means is placed in the blow gun between the valve means and the nozzle.

United States Patent r1 1 Malec Nov. 27, 1973 ASPIRATOR NOZZLE FOR BLOWGUNS OR THE LIKE Inventor:

Filed: Jan. 17, 1972 Appl. No.2 218,432

57 ABSTRACT An aspirator nozzle for a blow gun is disclosed herein. Thenozzle includes an air passageway extending from the inlet end to theoutlet end thereof. The nozzle also includes an aspirator bore whichextends through the nozzle transversely to the air passageway and whichcommunicates therewith. The preferred embodiment utilizes a singleaspirator bore which extends com- [52] U.S. Cl 239/124, 239/429, 239/58651 Int. Cl B05b 7/08 Pletely hreugh the transversely the [58] Field ofSearch 239/124 126 288-3 sageway. A modified form of the nozzle utilizesa plu- 525 rality of aspirator bores which extend radially outwardly andrearwardly from the air passageway. In [56] References Cited both of theembodiments, the aspirator bore communicates with the air passageway at.the location UNITED STATES PATENTS wherein the air flow has the greatestvelocity as it 3,129,892 4/1964 Tillman 239/4l7.3 passes through thenozzle h nozzle may be used 3 8/1966 {2 5 et i with a blow gun having apressure regulated, manually ggi zg z gg g 234/288 3 operated valving.The nozzle may also be used with a blow gun having a poppet type,manually operated FOREIGN PATENTS OR APPLICATIONS valve means. In thelatter environment, an air restric- 885,892 11/1971 Canada 239/525 tormeans is placed in the blow gun between the valve means and the nozzle.Primary Examiner-M. Henson Wood, Jr. Assistant Examiner-A. Kashnikow 9Chums 5 Drawmg figures Att0rneyZarley, McKee & Thomte I 1 I v 40 I 54 50M 1 /Z 5 7 4a Z8 Z Z0 l l1 /0 Z Z I W s ll 40 i "if? 32 I 1 NV :1 Li T IASPIRATOR NOZZLE FOR BLOW GUNS OR THE LIKE This invention relates toduster or blow guns which are used for cleaning, dusting or drying inindustrial environments. The gun is essentially a valve that is handactuated and which is attached to a compressed air line. The valve bodyhas a nozzle or orifice commonly used to direct the air in a usablecoherent pattern somewhat like cone projecting from the nozzle end ororifice end of the gun.

Recent federal and state laws are now in effect which regulate the useof the blow guns described above. The federal regulations provide thatan acceptable gun for use must not provide more than thirty P.S.I.static pressure at its nozzle or outlet orifice when the air dischargenozzle is blocked. Additionally, the noise made by the discharge of theacceptable g un when being used must not exceed 85 Decibels when testedunder certain prescribed conditions. v

A great many blow guns have been newly constructed and a great number ofold guns havebeen modified in-an attempt to meet the federalrequirements. The most common modification is a change in the nozzledesign of the guns which permits the nozzle configuration to pick upadditional air at atmospheric pressure by the positioning of the highpressure gun discharge orifice in a screened or guarded tube or shield.This effectively places the high pressure discharge port away from thepossibility of being blocked, even on purpose, and allows the screen orguard to discharge air rearwardly if the front of the tube or safetynozzle is blocked.

There have also been attempts to incorporate a small (usually pistontype) regulator in the handle of the blow gun replacing the usual poppetvalve mechanism and safety nozzle. The regulator is used to regulate thedischarged air to a conventional single orifice discharge port to 30P.S.I. Almost all of these safety guns of all types are commonly ratedat 100 P.S.I. input air pressure. Normally the static pressure of ablock nozzle, when the input reaches 150 P.S.I. allows a higher than 30P.S.I. output pressure. This is prevalent even with the auxiliary nozzleor safety nozzle utilized onmost guns that claim compliance with thefederal regulations.

Universally the new safety guns that allegedly meet the new Federalregulations have one common failing. The guns either diffuse the airstream too much for effective pinpoint cleaning with the air jet or ifthe gun is a single orifice type with the regulator, the volume of airis too low for effective usage.

therein which permits the blow gun to meet Federal requirements.

A further object of this invention is to provide an improved aspiratornozzle which does not substantially increase the cost of the blow gun.

A further object of this invention is to provide an aspirator nozzlewhich may be used in conjunction with a restrictor means which ismounted in a blow gun having a poppet type, manually operated valvemeans.

A further object of this inventionis to provide an improved aspiratornozzle including an aspirator port which communicates with the airpassageway in the nozzle at the point in which the air is traveling atthe greatest velocity through the nozzle.

A further object of this invention is to provide an aspirator nozzlewhich may be used with blow guns having a pressure regulated, manuallyoperated valve means thereon.

A still further object of this invention is to provide a nozzle which iseconomical of manufacture, durable in use and refined in appearance.

These and other objects will skilled in the art.

This invention consists in the construction, arrangements andcombination of the various parts of the device, whereby the objectscontemplated are attained as hereinafter more fully set forth,specifically pointed out in the claims, and illustrated in theaccompanying drawings, in which:

FIG. 1 is a sectionalview of a blow gun utilizing the nozzle of thisinvention:

FIG. 2 is a cross section of the nozzle:

FIG. 3 is a front elevational view of the nozzle:

be apparent to those FIG. 4 is a view similar to FIG. 1 except that theblow gun utilizes a poppet valve assembly; and

FIG. 5 is a perspective view of a modified form of the nozzle.

The aspirator nozzle of this invention is generally designated by thereference numeral 10. The numeral 12 refers to a blow gun having apressure regulated,

manually controlled valve means 14. The numeral 16- refers to a blow gunhaving a manually operated valve means 18 of the poppet type.

Blow gun 12includes a body '20 having internally threaded discharge andinlet ends 22 and 24 respectively. As seen in the drawings, nozzle 10 isthreadably received by the discharge end 22. Inlet end 24 is Normallybefore the passage of Federal laws restricting their usage, blow gunsuniversally embodied a single handle with a poppet valve button or leverwhich actuated discharging air through a single orifice. This orificewas most commonly made in a separate tip or adapted to be connected to asuitable air line or conduit connected to a source of air pressure.

Valve chamber 26 extends downwardly into body 20 as seen in FIG. 1.Opening 28 provides communication between inlet end 24 and chamber 26while opening 30 provides communication between passageway 32 andchamber 26. Passageway 32 communicates with discharge end 22 as viewedin FIG. 1. The pressure regulated valve means 14 is of the rolling Oring type such as that disclosed in U.S. Pat. No. 3,586,291 which issuedJune 22, 1971. The valve 14 generally includes retum spring 34, valve35, rivet 36, mainspring 38, spring guide 40, valve 0 ring 42, cartridge44, cartridge seals 46 and 48, retainer ring 50 and button 52. Lever 54is pivotally connected to gun body 20 at 56 and is adapted to depressbutton 52, uopon being depressed itself, to permit the flow of air frominlet end 24 to passageway 32.

Nozzle 10 has an air passageway or bore 58 extending from its rearwardor inlet end 60 to its forward or discharge end 62. As seen in FIG. 2,the rearward end of bore 58 is tapered or flared outwardly. Nozzle alsohas an aspirator bore or passageway 64 formed therein which extendscompletely through the nozzle transversely to the bore 58. Preferably,the diameter of bore 64 should be greater than the diameter of bore 58to achieve the most satisfactory results. It is important that the bore64 communicate with the bore 58 at the most reduced diameter of the boreso that the aspirator bore 64 communicates with the bore 58 at the pointof the greatest air velocity therethrough.

The blow gun 16 is essentially the same as blow gun 12 except that thepoppet valve assembly is utilized rather than the pressure regulatedvalve used in blow gun 12. When the nozzle 10 is being used on a blowgun such as illustrated in FIG. 4, it is necessary to insert an airrestrictor means 66 in passageway 32'. Air restrictor means 66 isremovably inserted into passageway 32' and has an 'air passageway bore68 extending therethrough. Bore 68 has a diameter which is substantiallysmaller than the diameter of passageway 32.

With respect to the blow gun 16, the normal method of modification andoperation is as follows. The nozzle 10 is removed from the gun body 20and a secondary orifice (restrictor means 66) is introduced into thepassageway 32 between the nozzle 10 and the poppet valve used to controlthe air. The air restrictor means 66 effectively reduces the amount ofair available at the tip from the previous unrestricted passage. Thepassageway 64 is then drilled or milled in the nozzle-10 at right anglesto the passageway 58; The position of the pas-- sageway 64 must becarefully positioned in the nozzle so that it crosses the passageway 58at somewhere in its reduced area. If not properly positioned, the crosshole or passageway 64 merely adds to the air which is lost and does notadd to the effectiveness of the gun. A normally non-complying blow gunwhen modified as just described may be operated at 150 P. S. l. and willnormally read the full line pressure or 150 P.S.I. when engaged at thenozzle end when the nozzle is blocked so that the gun does comply withthe Federal regulations. When the blow gun valve device is actuated, thenozzle discharges air at a lesser velocity and noise level than anunmodified unit. Virtually all of the air (approximately 95 percent) isstill discharged through the normal discharge end of the nozzle. Noappreciable amount of air escapes from the passageway 64 during normalgun operation. This is due to the increased velocity of the outwardlypassing air as it passes through the discharge orifice and the Coanda"effect of the airstream as it passes through the discharge orifice.

passageway 64 during normal gun operation to keep the passageway 64 freeof grease, paint, dirt, etc. that will build up in other design orificesor auxiliary air screens or nozzle devices.

It can readily be seen by the simple addition of an aspirator port in analready existing nozzle and a restrictor means pressed or screwed intothe passageway 32', non-complying guns may be modified so as to complywith the Federal regulations. This modification permits practically allexisting guns to be modified so as to meet Federal requirements.

The gun 12 operates in substantially the same manner as the blow gun 16except that a restrictor means is not needed in passageway 32 due to theutilization of the pressure regulated valve means. The nozzle 10functions in the same manner as the nozzle on the gun 16.

FIG. 5 illustrates a modified form of the nozzle 10 which is designatedby the reference numeral 10. Nozzle 10' has a passageway 58 (identicalto passageway 58) extending therethrough. A plurality of radiallyextending aspirator ports 70 extend outwardly from bore 58' tocommunicate with the atmosphere. It is preferred that the ports 70 bedisposed transversely with respect to the passageway 58' but they mayextend radially outwardly and rearwardly as seen in FIG. 5. Preferably,the ports 70 have a cumulative diameter greater than the diameter ofpassageway 58'.

It should be noted that FIG. 4 illustrates a modification of the forwardend of the guns. The gun 16 (or gun 12) is modified to provide acounterbore 72 which communicates with passageway 32'. A pair of slots74 and 76-are also formed in the end of the gun 16 to provideatmospheric communication for the counterbore 72. The counterbore 72 andslots 74 and 76 aid in exhausting the air to the atmosphere if thedischarge end of bore 58 is blocked.

FIG. 2 also illustrates that the bore 64 is formed in thev nozzle at thejuncture of the hex portion and the threaded portion of the nozzle. Sucha configuration provides an additional safety feature for the nozzlesince it is extremely difficult for the outer ends of the bore 64 to beintentionally plugged due to the unusual configuration thereof. 7

In each of the nozzle embodiments, the aspirator pas- I sageway or portscommunicate with the primary nozzle When the discharge end of the nozzleis blocked, the I passageway 64 becomes a discharge port and the airescapes outwardly at right angles from the blocked nozzle tip therebycomplying with Federal regulations.

With most of the air available in a coherent small pattern and the noiselevel reduced by the internal restrictor orifice thereby reducing theair passage to a lower point, the cross drilled nozzle meets Federalspecifications. The nozzle provides a blocked discharge port pressure of30 P.S.I. and does not waste or diffuse the air consumed or dischargedby the blow gun device. The passageway 64 may be of any cross-sectionalconfiguration but the preferred cross-sectional configuration iscircular. A further important feature in the cross drilled passageway 64is that the proper positioning of the same permits just enough air toescape through the passageway at the point of greatest air velocitypassing therethrough. The nozzles of this invention permit new as wellas existing blow guns to comply with the new Federal specifications andregulations regarding blow guns. The blow guns will not exceed theprescribed air pressure when the nozzle tips or discharge openings ofthe nozzles are blocked since the air pressure in the gun will beaspirated through the aspirator passageway or ports. Thus it can be seenthat the invention accomplishes at least all of its stated objectives.

I claim: 1. An aspirator nozzle comprising, said nozzle having a forwardend, and a rearward end adapted to be secured to the discharge end of anair gun body, said nozzle having an air passageway formed thereinextending therethrough from its rearward end to its forward end definingan inlet opening and a discharge opening, said nozzle having anaspirator passageway means formed therein between the rearward andforward ends thereof which communicates with said air passageway andwhich provides communication between said air passageway and theatmosphere,

said aspirator passageway communicating with said air passageway at thepoint of greatest air velocity.

tween said inlet opening and said valve chamber, said gun body having asecond air passageway means extending between said discharge opening andsaid valve chamber,

a manually operable valve means in said valve chamber for permitting theselective flow of air from said first air passageway means to saidsecond air passageway means,

an aspirator nozzle operatively secured to said gun body at said secondend, said nozzle having an inlet adapted to be secured to the dischargeend of an air gun body, said nozzle having an air passageway formedtherein extending therethrough from its rearward end to its forward enddefining an inlet said gun body having a valve chamber formed thereinbetween said first and second ends, said gun body having a first airpassageway means extending beopening in communication with said secondair passageway means, said nozzlevhaving an air discharge opening, saidnozzle having a first elongated bore extending therethrough between itsinlet and opening and a discharge opening, said nozzle havl5 dischargeopenings whereby air under pressure will ing an aspirator passagewaymeans formed therein normally be discharged from said dischargeopenbetween the rearward and forward ends thereof ing when said valvemeans is opened, said nozzle which communicates with said air passagewayand having an aspirator passageway means formed which providescommunication between said air therein between said inlet and outletopenings passageway and the atmosphere, I which communicates with saidfirst bore and the said aspirator passageway having a diameter greateratmosphere,

than the diameter of said air passageway. said aspirator passagewaymeans being transversely 4. In combination, disposed with respect tosaid first bore,

a blow gun body having first and second ends with an said aspiratorpassageway means comprises a single inlet opening at said first end anda discharge open-, elongated bore extending completely through said ingat said second end, said inlet opening being in nozzle, communicationwith a source of air under pressure, said nozzle having a hexagonalportion and a reduced said gun body having a valve chamber formedtherein diameter threaded portion extending therefrom, between saidfirst and second ends, said gun body said single elongated bore beingpositioned at the having a first air passageway means extendingbejuncture of said hexagonal portion and said tween said inlet openingand said valve chamber, threaded portion. said gun body having a secondair passageway 6. In combination, means extending between said dischargeopening a blow gun body having first and second ends with an and saidvalve chamber, inlet opening at said first end and a discharge openamanually operable valve means in said valve chaming at said second end,said inlet opening being in ber for permitting the selective flow of airfrom said communication with a source of air under pressure, first airpassageway means to said second air passaid gun body having a valvechamber formed therein sageway means, between said first and secondends, said gun body and an aspirator nozzle operatively secured to saidhaving a first air passageway means extending begun body at said secondend, said nozzle having an 40 tween said inlet opening and said valvechamber, inlet opening in communication with said second said gun bodyhaving a second air passageway air passageway means, said nozzle havingan air dismeans extending between said discharge opening charge opening,said nozzle having a first elongated and said valve chamber, boreextending therethrough between its inlet and a manually operable valvemeans in said valve chamdischarge openings whereby air under pressurewill ber for permitting the selective flow of air from said nonnally bedischarged from said discharge openfirst air passageway means to saidsecond air pas-' ing when said valve means is opened, said nozzlesageway means, having an aspirator passageway means formed and anaspirator nozzle operatively secured to said therein between said inletand outlet openings gun body at said second end,said nozzle having anwhich communicates with said first bore and-the inlet opening incommunication with said second atmosphere, I air passageway means, saidnozzle having an air dissaid aspirator passageway means beingtransversely charge opening, said nozzle having a first elongateddisposed with respect to said first bore, bore extending therethroughbetween its inlet and said aspirator passageway means comprises a singledischarge openings whereby air under pressure will elongated boreextending completely through said normally be discharged from saiddischarge opennozz'le, ing when said valve means is opened, said nozzlethe diameter of said single elongated bore having a having an aspiratorpassageway means formed diameter greater than the diameter of said firsttherein between said inlet and outlet openings elongatedbore. whichcommunicates with said first bore and the 5. In combination, atmosphere,

a blow gun body having first and second ends with an said aspiratorpassageway means being transversely inlet opening at said first end anda discharge opendisposed with respect to said first bore, ing at saidsecond end, said inlet opening being in said gun having a counterboreand slot means formed communication with a source' of air underpressure, at its second end.

7. In combination, a blow gun body having first and second ends with aninlet opening at said first end and a discharge opening at said secondend, said inlet opening being in communication with a source of airunder pressure, said gun body having a valve chamber formed thereinbetween said first and second ends, said gun body having a first airpassageway means extending between said inlet opening and said valvechamber, said gun body having a second air passageway means extendingbetween said discharge opening and said valve chamber,

a manually operable valve means in said valve chamber for permitting theselective flow of air from said first air passageway means to saidsecond air passageway means,

and an aspirator nozzle operatively secured to said gun body at saidsecond end, said nozzle having an inlet opening in communication withsaid second air passageway means, said nozzle having an air dischargeopening, said nozzle having a first elongated bore extendingtherethrough between its inlet and discharge openings whereby air underpressure will normally be discharged from said discharge opening whensaid valve means is opened, said nozzle having an aspirator passagewaymeans formed therein between said inlet and outlet openings whichcommunicates with said first bore and the atmosphere,

said aspirator passageway means being transversely disposed with respectto said first bore, I

said aspirator passageway means comprising a single elongated boreextending completely through said nozzle,

said valve means comprising a poppet valve, said second air passagewayhaving a diameter substantially greater than said first elongated borein said nozzle, and a restrictor means in said second air passageway,said air restrictor means having an air passageway formed thereinextending therethrough which has a diameter substantially smaller thanthe I 9. In combination, a blow gun body having first and second endswith an inlet opening at said first end and a discharge open-' ing atsaid second end, said inlet opening being in communication with a sourceof air under pressure,

said gun body having a valve chamber formed therein between said firstand second ends, said gun body having a first air passageway meansextending between said inlet opening and said valve chamber, said gunbody having a second air passageway means extending between saiddischarge opening and said valve chamber,

a manually operable valve means in said valve chamber for permitting theselective flow of air from said first air passageway means to saidsecond air passageway means,

and an aspirator nozzle operatively secured to said gun body at saidsecond end, said nozzle having an inlet opening in communication withsaid second air passageway means, said nozzle having an air dischargeopening, said nozzle having a first elongated bore extendingtherethrough between its inlet and discharge openings whereby air underpressure will normally be discharged from said discharge opening whensaid valve means is opened, said nozzle having an aspirator passagewaymeans formed therein between said inlet and outlet openings whichcommunicates with said first bore and the atmosphere, I

said aspirator passageway means being transversely disposed with respectto said first bore,

said aspirator passageway means comprising a single elongated boreextending completely through said nozzle,

said valve means comprising a pressure regulated valve means, saidpressure regulator valve means comprising a rolling O-ring type pressureregulator.

1. An aspirator nozzle comprising, said nozzle having a forward end, anda rearward end adapted to be secured to the discharge end of an air gunbody, said nozzle having an air passageway formed therein extendingtherethrough from its rearward end to its forward end defining an inletopening and a discharge opening, said nozzle having an aspiratorpassageway means formed therein between the rearward and forward endsthereof which communicates with said air passageway and which providescommunication between said air passageway and the atmosphere, saidaspirator passageway communicating with said air passageway at the pointof greatest air velocity.
 2. The nozzle of claim 1 wherein the diameterof said air passageway rearwardly of said aspirator passageway is equalto the diameter of said air passageway forwardly of said aspiratorpassageway.
 3. An aspirator nozzle comprising, said nozzle having aforward end, and a rearward end adapted to be secured to the dischargeend of an air gun body, said nozzle having an air passageway formedtherein extending therethrough from its rearward end to its forward enddefining an inlet opening and A discharge opening, said nozzle having anaspirator passageway means formed therein between the rearward andforward ends thereof which communicates with said air passageway andwhich provides communication between said air passageway and theatmosphere, said aspirator passageway having a diameter greater than thediameter of said air passageway.
 4. In combination, a blow gun bodyhaving first and second ends with an inlet opening at said first end anda discharge opening at said second end, said inlet opening being incommunication with a source of air under pressure, said gun body havinga valve chamber formed therein between said first and second ends, saidgun body having a first air passageway means extending between saidinlet opening and said valve chamber, said gun body having a second airpassageway means extending between said discharge opening and said valvechamber, a manually operable valve means in said valve chamber forpermitting the selective flow of air from said first air passagewaymeans to said second air passageway means, and an aspirator nozzleoperatively secured to said gun body at said second end, said nozzlehaving an inlet opening in communication with said second air passagewaymeans, said nozzle having an air discharge opening, said nozzle having afirst elongated bore extending therethrough between its inlet anddischarge openings whereby air under pressure will normally bedischarged from said discharge opening when said valve means is opened,said nozzle having an aspirator passageway means formed therein betweensaid inlet and outlet openings which communicates with said first boreand the atmosphere, said aspirator passageway means being transverselydisposed with respect to said first bore, said aspirator passagewaymeans comprises a single elongated bore extending completely throughsaid nozzle, the diameter of said single elongated bore having adiameter greater than the diameter of said first elongated bore.
 5. Incombination, a blow gun body having first and second ends with an inletopening at said first end and a discharge opening at said second end,said inlet opening being in communication with a source of air underpressure, said gun body having a valve chamber formed therein betweensaid first and second ends, said gun body having a first air passagewaymeans extending between said inlet opening and said valve chamber, saidgun body having a second air passageway means extending between saiddischarge opening and said valve chamber, a manually operable valvemeans in said valve chamber for permitting the selective flow of airfrom said first air passageway means to said second air passagewaymeans, an aspirator nozzle operatively secured to said gun body at saidsecond end, said nozzle having an inlet opening in communication withsaid second air passageway means, said nozzle having an air dischargeopening, said nozzle having a first elongated bore extendingtherethrough between its inlet and discharge openings whereby air underpressure will normally be discharged from said discharge opening whensaid valve means is opened, said nozzle having an aspirator passagewaymeans formed therein between said inlet and outlet openings whichcommunicates with said first bore and the atmosphere, said aspiratorpassageway means being transversely disposed with respect to said firstbore, said aspirator passageway means comprises a single elongated boreextending completely through said nozzle, said nozzle having a hexagonalportion and a reduced diameter threaded portion extending therefrom,said single elongated bore being positioned at the juncture of saidhexagonal portion and said threaded portion.
 6. In combination, a blowgun body having first and second ends with an inlet opening at saidfirst end and a discharge opening at said second end, said inlet openingbeing in communication with a source of air under pressure, said gunbody having a valve Chamber formed therein between said first and secondends, said gun body having a first air passageway means extendingbetween said inlet opening and said valve chamber, said gun body havinga second air passageway means extending between said discharge openingand said valve chamber, a manually operable valve means in said valvechamber for permitting the selective flow of air from said first airpassageway means to said second air passageway means, and an aspiratornozzle operatively secured to said gun body at said second end, saidnozzle having an inlet opening in communication with said second airpassageway means, said nozzle having an air discharge opening, saidnozzle having a first elongated bore extending therethrough between itsinlet and discharge openings whereby air under pressure will normally bedischarged from said discharge opening when said valve means is opened,said nozzle having an aspirator passageway means formed therein betweensaid inlet and outlet openings which communicates with said first boreand the atmosphere, said aspirator passageway means being transverselydisposed with respect to said first bore, said gun having a counterboreand slot means formed at its second end.
 7. In combination, a blow gunbody having first and second ends with an inlet opening at said firstend and a discharge opening at said second end, said inlet opening beingin communication with a source of air under pressure, said gun bodyhaving a valve chamber formed therein between said first and secondends, said gun body having a first air passageway means extendingbetween said inlet opening and said valve chamber, said gun body havinga second air passageway means extending between said discharge openingand said valve chamber, a manually operable valve means in said valvechamber for permitting the selective flow of air from said first airpassageway means to said second air passageway means, and an aspiratornozzle operatively secured to said gun body at said second end, saidnozzle having an inlet opening in communication with said second airpassageway means, said nozzle having an air discharge opening, saidnozzle having a first elongated bore extending therethrough between itsinlet and discharge openings whereby air under pressure will normally bedischarged from said discharge opening when said valve means is opened,said nozzle having an aspirator passageway means formed therein betweensaid inlet and outlet openings which communicates with said first boreand the atmosphere, said aspirator passageway means being transverselydisposed with respect to said first bore, said aspirator passagewaymeans comprising a single elongated bore extending completely throughsaid nozzle, said valve means comprising a poppet valve, said second airpassageway having a diameter substantially greater than said firstelongated bore in said nozzle, and a restrictor means in said second airpassageway, said air restrictor means having an air passageway formedtherein extending therethrough which has a diameter substantiallysmaller than the diameter of said second air passageway.
 8. Thecombination of claim 7 wherein said air restrictor means is removablymounted in said second air passageway.
 9. In combination, a blow gunbody having first and second ends with an inlet opening at said firstend and a discharge opening at said second end, said inlet opening beingin communication with a source of air under pressure, said gun bodyhaving a valve chamber formed therein between said first and secondends, said gun body having a first air passageway means extendingbetween said inlet opening and said valve chamber, said gun body havinga second air passageway means extending between said discharge openingand said valve chamber, a manually operable valve means in said valvechamber for permitting the selective flow of air from said first airpassageway means to said second air passageway means, And an aspiratornozzle operatively secured to said gun body at said second end, saidnozzle having an inlet opening in communication with said second airpassageway means, said nozzle having an air discharge opening, saidnozzle having a first elongated bore extending therethrough between itsinlet and discharge openings whereby air under pressure will normally bedischarged from said discharge opening when said valve means is opened,said nozzle having an aspirator passageway means formed therein betweensaid inlet and outlet openings which communicates with said first boreand the atmosphere, said aspirator passageway means being transverselydisposed with respect to said first bore, said aspirator passagewaymeans comprising a single elongated bore extending completely throughsaid nozzle, said valve means comprising a pressure regulated valvemeans, said pressure regulator valve means comprising a rolling O-ringtype pressure regulator.